Translation array - c

Question

I need to make a simple translator. For example:
input: "foo" output: "bar"
input: "the" output: "teh"
input: "what" output: "wut"
I know I can write it like this:
if (!strcmp(input, "foo"))
puts("bar");
else if (!strcmp(input, "the"))
puts("teh");
else if (!strcmp(input, "what"))
puts("wut");
But that's big and messy. Is there a shortcut to do this? I know that in PHP (sorry for the inevitable syntax errors, I'm not proficient) there's something like this:
value = array(
"foo" => "bar",
"the" => "teh",
"what" => "wut"
);
How can I shorten the original code using something like a PHP array?

Answer 1

You can define a struct, which contains the word and the translation:
typedef struct {
const char *word;
const char *translation;
} translate_t;
Then you can just create an array of structs like this:
const translate_t translate[] = {{"foo", "bar"},
{"the", "teh"},
{"what", "wut"}};
If you want print out the words and translations, then you can just do this:
size_t size = sizeof translate/sizeof *translate;
for (size_t i = 0; i < size; i++) {
printf("Word: %s Translation: %s\n", translate[i].word, translate[i].translation);
}
Which will output:
Word: foo Translation: bar
Word: the Translation: teh
Word: what Translation: wut
This is a good approach for associating a word with a translation.
UPDATE: #Olaf suggested using a macro for size, which is far better for declaring sizes of arrays. Therefore, the above code can be expressed as:
#define ARRAY_SIZE(x) ((sizeof x)/sizeof *x) /* near top, or before main() is a good place for this */
for (size_t i = 0; ARRAY_SIZE(translate); i++) {
printf("Word: %s Translation: %s\n", translate[i].word, translate[i].translation);
}

Answer 2

Found it out:
const char *Translate[] = {
"foo", "bar",
"the", "teh",
"what", "wut"
};
int t_idx(char *s)
{
int i;
for (i = 0; Translate[i]; i += 2)
if (!strcmp(Translate[i], s))
return i+1;
return -1;
}
const char *translate(char *s)
{
int idx = t_idx(s);
return (idx == -1) ? s : Translate[idx];
}
Return values of translate:
translate("what") = "wut"
translate("some") = "some"
translate("foo") = "bar"

Answer 3

There are no map or associative array types in standard C; you must implement it yourself. A simple idea would be to use a struct:
#include <string.h>
#include <stdio.h>
struct map {
struct map_elem {
char *key;
char *value;
} * elem;
size_t size;
};
int main(void) {
struct map_elem map_elem[] = {
{"foo", "bar"}, {"the", "teh"}, {"what", "wut"}};
struct map const map = {map_elem, sizeof map_elem / sizeof *map_elem};
char input[] = "foo";
for (size_t i = 0; i < map.size; i++) {
struct map_elem *elem = map.elem + i;
if (strcmp(input, elem->key) == 0) {
puts(elem->value);
break;
}
}
}
Of course, it's just a little example.